How can I know all possible reactions from a set of elements to an other?

Question

What is the simplest software that calculates it?

Answer 1

You have not given enough precision

In general you look the outer shell or valence shell of the element.

These shells are completred with 8 elctrons except the first completed with 2 electrons

Elements with 8 electrons on this shell are noble gases. They are inert in most of cases

Elements with 6 or 7 electrons tend to catch one or two electrons to fill the shell

Elements with few electrons tend to give these electrons

Answer 2

For many elements there is only one oxidation state that they exhibbit so there is only one combination for a compound. In otheres take the various oxidation possibilities. In organic compounds there is a never ending set of possibilities. The law of multiple proportions.

Answer 3

By looking at the chemical properties of an element from the other.